In conventional keyboards, a key switch structure is known which, in order to light up a character or the like on a key top, projects light onto the back side of the key top from a light emitting portion of a back plate placed on the underside of the key top, to thereby light up a character or a symbol, for example, of a key switch (e.g., see JP-A No. 2008-235065 and JP-A No. 2011-18484).
This type of key switch structure is equipped with a link mechanism that supports the key top in such a way that the key top can be pressed, and the link mechanism is supported by supports members that are disposed on the back plate and comprise a material that transmits light.